High power solar panels can interrupt in an emergency

According to Steve Drumm, European Marketing, Sales Development and Project Management, Omron: “Rooftop solar panels are becoming increasingly popular in offices and homes, and as a result the issue of their shut-down in the event of a fire in the building is moving up the agenda. Rapid PV shut-down is moving from being highly desirable to mandatory in some markets in order to protect fire fighters and other first responders.”

In response, Omron has launched the G7L-X relay, with a rated load of 1,000VDC at 25A and a release time of 30ms. This relay can be installed close to a PV panel or other renewable source, and disconnect it quickly in an emergency, to permit maintenance or in response to utility requests. The G7L-X conforms to UK and IEC solar inverter standards, as well as applicable UL and VDE electrical standards.

Features of the design include an assisting magnetism circuit to help achieve a very quick switchover. The relay contacts have been specifically designed to handle the very high DC loads that are a feature of this application, and have a contact gap of 6.0mm for safety.

The G7L-X is rated at 6,000 operations at 600VDC, and 100 operations at 1000VDC – more than enough for its envisaged emergency cut-off application. The device is compact for a relay with this capacity: it’s size is 52.5x35.5x41.0mm. The relay is suitable for outdoor installations, and can operate in ambient temperatures of between -40 and 85°C. Omron is also offering a general purpose version of the relay, with a capacity of 20A at 1,000VDC.